1. Field of the Invention
Embodiments of the present invention relate to an amnion insertion device to push a bulged amnion back into a uterine cavity during an urgent cervical cerclage operation. More particularly, embodiments of the present invention relate to an amnion insertion device by which a bulged amnion is pushed back into the uterine cavity without damaging the bulged amnion using a dilation balloon inflated by air applied through an air injection tube fitted in an external tube while being integrated with the external tube and an air communication hole, and then a cervix is stitched up, to treat cervical incompetence, and in which the dilation balloon formed at a front end portion of the air injection tube is not deformed or pushed backwards when pushing the bulged amnion back into the uterine cavity, to facilitate an urgent cervical cerclage operation, and in which the external tube and air injection tube are integrated with each other, so that the amnion insertion device may be entirely gripped by one hand of an operator, leaving the other hand available to be used for stitching up the cervix, thereby maximizing efficiency of the cervical cerclage operation.
2. Related Prior Art
As well known, cervical incompetence is a medical condition in which a pregnant woman's cervix begins to efface due to a functional or structural defect of the cervix without pain or bleeding before the fetus has reached term. Thus, cervical incompetence may cause the amnion to bulge out of the uterine cavity, resulting in miscarriage or preterm birth during the second and third trimesters. Occurrence rate of cervical incompetence is 0.1% to 2% for all pregnant women. 15% of all preterm births occurring at 16 to 28 weeks gestational age are due to cervical incompetence. Thus, cervical incompetence is closely related to a morbidity or death rate of new born babies.
Medical treatment for cervical incompetence includes preventive cervical cerclage operation or urgent cervical cerclage operation carried out when a length of the cervix is observed to be short in an ultrasonic detection.
Although the cervix effaces, this may not be noticed of or diagnosed. Thus, an appropriate preventive cerclage operation or urgent cerclage operation may not be executed in time. In this case, the amnion bulges out of the uterine cavity and a delivery inevitably occurs.
In the case of cervical incompetence where the cervix effaces and the amnion bulges out of the uterine cavity, the urgent cerclage operation may be executed as the best approach. In the urgent cerclage operation, the bulged amnion is pushed back into a uterine cavity and then the cervix is stitched up.
Conventional methods for pushing the bulged amnion back into the uterine cavity include a trendelenburg position method, a method of injecting a saline solution into a bladder and a method of inserting the amnion into the uterine cavity using a sponge forcep or foley catheter.
In the trendelenburg position method, the amnion naturally moves back into the uterine cavity by lifting up feet while the patient lies on her back. In the method of injecting a saline solution into a bladder, a given amount of the saline solution is injected into the bladder so that the amnion is pushed back up by the injected saline solution. In the method using the sponge forcep, an operator pinches wet gauze using the sponge forcep and directly pushes the amnion back into the uterine cavity.
Among such cervical cerclage methods, the method using the sponge forcep has mainly been used. In this method, the amnion may be damaged due to sharpness of the gauze. The amnion may be again bulged out of the uterine cavity particularly when drawing the wet gauze out of the uterine cavity after pushing the amnion into the uterine cavity.
The conventional method using the foley catheter may be valid when the cervix opens to a small extent. However, when the amnion bulges out of the uterine cavity, it is difficult to push the amnion back into the uterine cavity because the foley catheter may be bendable.
Recently, to solve such problems, Korean Patent No. 710905 discloses an amnion insertion device including, as shown in FIG. 1, an air injection tube 10 to inject air through operation of an air injection means 12 formed at a rear end of the air injection tube 10, a dilation balloon 30 formed at a front end of the air injection tube 10 to be inflated by air injected through the air injection tube 10 and thus to directly push a bulged amnion back into a uterine cavity; a guide pipe 40 to receive the air injection tube 10 at other region than a dilation balloon 30 formation region and to allow the amnion to be easily inserted into the uterine cavity by preventing the air injection tube 10 from bending; an air hole 50 formed at one side of the air injection tube on which the dilation balloon 30 is formed, to communicate air injected through the air injection tube 10 to the dilation balloon 30. Especially, the dilation balloon 30 is characterized in that the dilation balloon 30 is fixed to the guide pipe 40 using an adhesive material in order that the dilation balloon 30 coming into an inflated state is prevented from moving left or right by a force generated when pushing the bulged amnion back into the uterine cavity.
In the amnion insertion device disclosed in Korean Patent No. 710905, the dilation balloon 30, as shown in FIG. 2, is configured be attached to an outer surface of a front end portion of the air injection tube 10. Accordingly, although the dilation balloon 30 is fixed to the guide pipe 40 at a rear end portion of the dilation balloon 30, the dilation balloon 30 may move left or right or be pushed backwards for a structural reason thereof during pushing the bulged amnion back into the uterine cavity. Thus, it is difficult to insert the bulged amnion back into the uterine cavity.
In the amnion device disclosed in Korean Patent No. 710905, the air injection tube 10 serving as an air channel to inject air into the dilation balloon 30, and the guide pipe 40 connected to an outer surface of the air injection tube 10 are not integrated with each other but are formed as individual components. Therefore, during a cervical cerclage process, a single operator should operate the amnion insertion device to push the bulged amnion back into the uterine cavity while gripping the guide pipe 40 of the amnion insertion device using one hand and gripping the air injection tube 10 using the other hand. Thus, in case when carrying out the cervical cerclage operation using the amnion insertion device disclosed in Korean Patent No. 710905, two operators may be necessary to operate the amnion insertion device and carry out the cervical cerclage operation respectively. As a result, this may cause waste of labor and further lead to an unexpected operation result in particular when the two operators do not effectively cooperate.
Moreover, in the amnion insertion device disclosed in Korean Patent No. 710905, there may occur a limitation as to dilation extent of the dilation balloon 30 because thickness of the dilation balloon 30 is very small and further the dilation balloon 30 moves left or right or is pushed backwards when pushing the bulged amnion back into the uterine cavity. In a certain case, the amnion excessively bulges out of the uterine cavity and hence the amnion may be damaged if the amnion is forcibly pushed back. In this case, in order to prevent the amnion from being damaged during the cervical cerclage process, amniocentesis should be carried out in advance to discharge some of amniotic fluid from the amnion and hence reduce the size of the amnion. After amniocentesis, the bulged amnion may be pushed back into the uterine cavity using the amnion insertion device. That is, before the cervical cerclage operation, the size of the amnion must be reduced.